Australian boat race protester Trenton Oldfield will be allowed to stay in the United Kingdom after an immigration tribunal judge said the activist had made a positive contribution to British society.

Mr Oldfield has successfully appealed a decision of Home Secretary Theresa May to deport him on the basis his presence in Britain was ‘‘not conducive to the public good’’.

Immigration tribunal Judge Kevin Moore will make his official determination within 10 days but told Monday’s tribunal hearing that he would be finding in favour of the 37-year-old.

The Oxford crew looks on as protester Trenton Oldfield disrupts the boat race between Oxford and Cambridge in 2012. Photo: Getty Images

‘‘It would be my intention to allow your appeal,’’ the judge told Mr Oldfield in London.

Advertisement

‘‘There is no doubt in my view to your character and the value you are to UK society generally.’’

Mr Oldfield told an immigration tribunal hearing that if he was deported from the UK his British wife and five-month-old baby daughter wouldn't move to Australia with him because it's a "racist country".

Oldfield's request for a visa was refused on the grounds his presence in Britain is not 'conducive to the public good'. Photo: Getty Images

He fronted the tribunal in London after his request for a spousal visa was refused by the government on the grounds his presence in Britain is not "conducive to the public good".

The 37-year-old activist has lived in the UK for more than 10 years.

In April 2012 Mr Oldfield swam into the path of the Oxford and Cambridge rowing crews, as they raced down the Thames, in a protest against elitism and inequality. He was subsequently jailed for seven weeks.

"Australia is a particularly racist country," Mr Oldfield said on Monday when explaining that if deported he would be separated from his wife Deepa Naik, 36, and child.

Mr Oldfield said Ms Naik had never visited Australia and couldn't live there because some Indians in the community had suffered violent racist attacks.

There was also everyday "passive water-cooler racism", he said.

"Our home is here. Australia is on the other side of the world."

Mr Oldfield told immigration judge Kevin Moore that if he were allowed to stay in the UK - which he said he loved - "I give you my word we won't be here (in a tribunal) again".

The Australian said when he swam in the Thames in 2012 he'd recently returned to the UK after caring for Ms Naik's father as he was dying of cancer.

He said he was saddened to realise that wealthier people could afford better drugs and have a better quality of life when gravely ill.

"I think I was vulnerable in terms of realising how short life can be," Mr Oldfield told the hearing before breaking down in tears.

"I think I was very emotional. When you walk around London you see pockets of deprivation that still exist. I think I was heartbroken."

His lawyer, Stephanie Harrison QC, said the boat protest wasn't of sufficient gravity or seriousness to justify his deportation.

"His presence is neither undesirable or contrary to the public good," she said, adding that separating him from his wife would be a "disproportionate" punishment.

Ms Harrison said the judge had "unfettered discretion" to overturn Home Secretary Theresa May's decision to kick him out of the country.